The present invention relates to a window sensing device with movement detection.
FIG. 1 shows a known magnetic sensing window arrangement 10 that includes a window frame 12 and a lower sliding window or lower window sash 14 in a partially open position. An upper window or upper window sash 16 is provided that is either fixed in place, or in some instances, also vertically movable. An upper magnet 20 and a lower magnet 22 are mounted vertically spaced onto an edge part of the lower sliding window 14. A magnetic sensor 24 is mounted to the window frame 12 upwardly from a lower corner of the lower sliding window 14 and near the magnets 20, 22. In the open position shown in FIG. 1, the lower magnet 22 is in alignment with the magnetic sensor 24 and thus is detected. Therefore, the magnetic sensor 24 can enable arming of an alarm system even though the window is in an open position. In a second closed position, the sliding window 14 is closed and the upper magnet 20 is adjacent to and in alignment with the magnetic sensor 24. Thus, the magnetic sensing window arrangement 10 enables arming of an alarm system both when the lower sliding window 14 is open a specific predetermined distance and when the lower sliding window 14 is closed. The magnetic sensing window arrangement 10 does not distinguish between the closed window position and the lower sliding window 14 being opened a predetermined distance.
One disadvantage of the known magnetic sensing window arrangement 10 is that the lower sliding window 14 must be aligned and maintained at the exact location shown in FIG. 1 so that the magnet 22 is adjacent the magnetic sensor 24. Another disadvantage is that the lower sliding window 14 can only be opened a set small amount. Another disadvantage is the requirement of two magnets 20, 22 in the prior art arrangement.